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ARRL Propagation Bulletin ARLP003 (2012)

SB PROP @ ARL $ARLP003
ARLP003 Propagation de K7RA

ZCZC AP03
QST de W1AW  
Propagation Forecast Bulletin 3  ARLP003
From Tad Cook, K7RA
Seattle, WA  January 20, 2012
To all radio amateurs 

SB PROP ARL ARLP003
ARLP003 Propagation de K7RA

New sunspot groups appeared on every day over the past reporting
week (January 12-18), until yesterday, January 19 which had no new
spots.

On January 12, new sunspot group 1396 appeared, and the next day two
more - 1397 and 1398 - popped into view. On January 14 four new
sunspot groups appeared: 1399, 1400, 1401 and 1402. January 15 saw
group 1391 vanish and new group 1403 emerge. Two more appeared
January 16 - 1404 and 1405 - while 1397 vanished. On January 17,
1406 appeared and 1395 disappeared while 1407 emerged on January 18.

Average daily sunspot numbers rose this week from 90.6 to 116.9, or
29%. But solar flux was about the same, changing from 134.9 to
133.4.

The latest prediction from USAF/NOAA has a solar flux of 150 on
January 20-21, 155 on January 22, 160 on January 23-27, 140 on
January 28-29, and 135 on January 30 through February 6. We are
still looking for a solar flux peak of 165 on February 17-21. The
predicted flux values of 160 on January 23-27 are markedly higher
than the 145 predicted last week for the same dates.

Predicted planetary A index is 6, 10, 8, 10 and 8 on January 20-24
and 5 on January 25 through February 1, 6 on February 2-4, and 5 on
February 5-8.

Roger Larson, KF6IVA of Harrison, Maine wrote and referred to errors
in the solar article in The Atlantic which was linked from last
week's Propagation Forecast Bulletin ARLP002. I think perhaps he is
referring to the article's statement that "Hydrogen, the lightest
element and the Sun's primary constituent, fuses to become Helium,
releasing energy."

Roger wrote: "The Sun converts 600 million tons of hydrogen to 596
million tons of helium every second. The missing 4 million tons of
matter are converted to energy by E = mc sq. The Sun is
approximately 4.6 billion years old and will live another 4.6
billion years as a yellow main sequence star. The Sun has become
about 30% more luminous since it began burning hydrogen (the faint
Sun paradox).  Earth's early atmosphere had more greenhouse gases
which allowed the surface temperature to be warm enough for life to
form. It is also thought that in 100 million years or so the Sun
will become more luminous and may cause Earth's temperature to
become too hot to support life. Currently the green house gases
raise the surface temperature about 60 degrees F. In 4.6 billion
years the core of the Sun will run out of hydrogen, the Sun will
begin to swell and the helium in the core will fuse to carbon and
oxygen. The Sun may swallow the Earth in its giant phase which will
last about 1 billion years. The Sun will never go supernova (it does
not have enough mass) nor will it be able to burn carbon or oxygen.
It will puff off its outer envelope and become a white dwarf."

We mentioned Belgian website http://www.spaceweatherlive.com in
Propagation Forecast Bulletin ARLP003 on January 22, 2010. If you
click on the Solar Activity link toward the top and select Sunspot
Regions from the drop-down, it takes you to
http://www.spaceweatherlive.com/en/solar-activity. When I see this
early Friday morning (1145 UTC) it lists seven regions (sunspot
groups) in the table and gives the number of sunspots in each.

You may recall from past bulletins that the daily sunspot number is
calculated by multiplying the number of regions by ten, then adding
one for each sunspot.  As there are 7 regions and 47 spots, the
sunspot number would be 70 plus 47, or 117. When I look at
http://www.swpc.noaa.gov/ftpdir/indices/DSD.txt I see that the
sunspot number for January 19 is 117.

If you click on the image of the Sun to the left of the table, it
takes you to
http://www.spaceweatherlive.com/en/solar-activity/sunspot-regions.
Here are details and recent images for each sunspot group. You can
also see details on these at
http://www.swpc.noaa.gov/ftpmenu/forecasts/SRS.html. Note the daily
reports are shown with the date for the following day. So the
January 19 report was issued in the early part of January 20, so it
gets a January 20 date.

Note the Space Weather Live site offers an email aurora alert at
http://www.spaceweatherlive.com/en/aurora-alertmail.

On Wednesday, Science Daily published a brief article on the Solar
Dynamics Observatory at
http://www.sciencedaily.com/releases/2012/01/120118203110.htm.

Charlie Carroll, K1XX of Grant, Florida (on Florida's East Coast,
about 70 miles southeast of Orlando) notes that the ARRL CW DX
Contest is February 18-19, right in the midst of that period
(February 17-21) in which NOAA predicts solar flux values of 165.
See http://www.arrl.org/arrl-dx for details on the contest. He is
looking forward to operating PJ4X in Bonaire for the contest, so he
is watching this prediction closely.

Jon Jones, N0JK wonders if a solar flux value of 165 in February is
a bit too optimistic.  He also wonders if Cycle 24 will have two
peaks like Cycle 23, the first peak being in November 2011. Jon
notes there was some good 6 meter sporadic-E skip on Wednesday night
(Thursday January 19, UTC time) around 0420-0530 UTC from Kansas and
Colorado into Mexico, and "east coast stations had Es to C6 with
link on to PY, LU, CE."

There seems to be energy from a solar flare headed our way; however,
on Thursday the prediction at
http://www.swpc.noaa.gov/ftpmenu/forecasts/45DF.html for January 19
showed planetary A index rising to 10 on Saturday (January 21), 8 on
Sunday, and 10 again on Monday. That doesn't seem like a large
effect, but perhaps Friday's forecast will be more dramatic.

MSNBC has a piece on the flare at
http://cosmiclog.msnbc.msn.com/_news/2012/01/19/10192639-solar-blast-heading-our-way
and National Geographic at
http://newswatch.nationalgeographic.com/2012/01/19/new-video-solar-flare-spied-on-candy-colored-sun/.
Also check Universe Today at
http://www.universetoday.com/92780/aurora-alert-sun-sends-cme-in-earths-direction/.

As always, http://www.spaceweather.com/ has frequent and timely
updates. On Thursday they said the flare was at 1630 UTC on January
19 and came from sunspot group 1401. Spaceweather.com mentioned an
impact centered on 2230 UTC on Saturday, January 21, with an
ambiguity of plus or minus seven hours.

Vic Alfonsi, WA6MCL of Corona, California was on 18.074 MHz running
100 watts on CW into a dipole at 1750 UTC on January 14. He said he
"was in QSO with Mitch NH6JC/M while he was in his vehicle watching
the Sun rise over the water on Kauai. He had good signal, usual 17
meter stuff, very strong but little signal meter reading. Very low
S/N. Many Midwest stations were calling him.

"After the QSO with Mitch, Bill, K2TQC called him and although very
strong here in Corona CA it was hard to copy. I quickly realized
that he had a very strong echo. His signal from Syracuse NY was 599
and his 1.5 second delay echo was 589. I moved him off freq. and he
confirmed same on me.

"I know in previous reports you mention that on 80 but never heard
that before on 18 MHz. His QRZ info says he runs power and loops so
he was not using a beam."

Vic thinks he and Bill may have heard both long path and short path
signals.

Victor Paul, WB0TEV of Greenville, Texas sent a link to the same
geomagnetic observatory from where until recently we received weekly
geomagnetic forecasts. The link is
http://www.ig.cas.cz/en/structure/observatories/geomagnetic-observatory-budkov/forecast-of-geomagnetic-activity/.

Unfortunately, the retiring staff member (F. Zloch) was the one who
actually wrote the predictions we used. Upon his recent retirement
after 34 years, nobody there is doing the same predictions.  At the
link referenced above, you can see local K index readings but the
only predictive function is the remark for the following day, such
as "Quiet" or "Unsettled to Active."

If you would like to make a comment or have a tip for our readers,
email the author at, k7ra@arrl.net.

For more information concerning radio propagation, see the ARRL
Technical Information Service web page at
http://arrl.org/propagation-of-rf-signals. For an explanation of the
numbers used in this bulletin, see
http://arrl.org/the-sun-the-earth-the-ionosphere. An archive of past
propagation bulletins is at
http://arrl.org/w1aw-bulletins-archive-propagation. Find more good
information and tutorials on propagation at
http://myplace.frontier.com/~k9la/.

Monthly propagation charts between four USA regions and twelve
overseas locations are at http://arrl.org/propagation.

Instructions for starting or ending email distribution of ARRL
bulletins are at http://arrl.org/bulletins.

Sunspot numbers for January 12 through 18 were 57, 81, 145, 141,
120, 152, and 122, with a mean of 116.9. 10.7 cm flux was 116.8,
124.1, 132.3, 133.5, 139.7, 139, and 148.1, with a mean of 133.4.
Estimated planetary A indices were 5, 6, 3, 3, 8, 5, and 4, with a
mean of 4.9. Estimated mid-latitude A indices were 5, 8, 3, 4, 8, 4,
and 4, with a mean of 5.1.
NNNN
/EX

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